Two U.S. companies, Pacific Fusion and General Atomics, are collaborating to test an innovative pulser module with the potential to revolutionize fusion energy. This first-of-its-kind, production-scale module is designed to store electrical energy and release it in powerful, precisely controlled bursts, driving small fuel containers to conditions where high-yield fusion can occur.
Powering Fusion: The Pulser Module Explained
A pulser module is a system that accumulates electrical energy and then discharges it in controlled, rapid bursts. The immense power released is intended to propel small fuel containers to high-yield fusion conditions, exceeding 100 megajoules. This process delivers the energy necessary for a target to reach the extreme temperatures and pressures required for fusion.
The pulser module relies on an impedance-matched Marx generator (IMG), a technology co-invented by Pacific Fusion’s cofounder and Chief Technology Officer, Keith LeChien. Multiple IMG modules combine to form a pulser capable of generating approximately 2 TW of peak power in a single, rapid pulse.
2TW: More Power Than the Entire US Grid?
Each pulser module, with a diameter of about 1.9 meters, can deliver approximately 2 TW of peak power in a single fast pulse. To put this in perspective, Pacific Fusion states that this is about four times more power than the average amount provided by the entire U.S. electrical grid. The company’s demonstration system is expected to store around 80 megajoules of electrical energy and deliver over 60 megaamperes in roughly 100 nanoseconds. This energy is then directed towards centimeter-scale deuterium-tritium fuel capsules, similar to laser-driven inertial confinement fusion.
Pacific Fusion and General Atomics: A Powerful Partnership
Pacific Fusion, established in 2023 and based in California, is focused on developing “a pulsed magnetic fusion system to achieve net facility gain”. This means creating a system where the energy output from fusion exceeds the energy input required to run the facility. General Atomics, a major player in fusion research, is collaborating with Pacific Fusion on this project. General Atomics is known for its Fusion Pilot Plant (FPP), announced in 2022, which aims to provide a detailed look into fusion technologies.
“GA’s engineering expertise remains an important part of our progress, and we expect this collaboration to continue through future phases of development,” said Keith LeChien, Pacific Fusion cofounder and chief technology officer.
Achieving Net Energy Gain: The Next Frontier
The ultimate objective is to achieve net facility energy gain, where the fusion energy output surpasses the energy stored in the capacitors. This milestone has not yet been reached and represents the next significant technological advancement in fusion power using Pacific Fusion’s approach. Pacific Fusion believes it needs around 150 of these pulsers to demonstrate its fusion system.
How it Works: The Science Behind the Pulser
The pulser modules store electricity in capacitors and release it in fast pulses. These pulses deliver energy with the help of metallic pulse tubes that accelerate towards the fusion chamber before imploding. The energy from multiple transmission lines is then coupled into two electrodes, which drive current through the target, electromagnetically compressing it to cause fusion.
Pacific Fusion’s IMG technology accounts for electromagnetic-wave propagation and “stacking waves,” delivering an intense, 100-nanosecond burst of energy. This differs from the “stacking voltage” approach used in conventional pulser technology. With IMG, internally reflected waves cancel out, leaving only forward-moving waves.
Key Advantages of Pacific Fusion’s Approach
- Modular Design: The pulser modules utilize modular components that can be mass-manufactured at a low cost.
- High Power Density: The design delivers the most power-dense, line-replaceable unit in fusion history.
- Efficient Energy Delivery: The triggering matches the speed of electromagnetic waves, resulting in approximately 90% efficiency in energy delivery.
- Simplified System: The IMG uses lower-voltage components and standard materials, making it safer, easier to assemble, and more cost-effective.
Timeline and Future Plans
Pacific Fusion plans to build 156 pulser modules into a demonstration system by 2030. The company successfully demonstrated the core components needed for the technology late last year, conducting 100 consecutive tests in a single day to validate system reliability.
The Promise of Fusion Energy
Fusion is the process that powers stars, releasing vast amounts of energy when two atomic nuclei combine. Fusion technology has the potential to provide a clean, sustainable, and virtually limitless energy source.
